Fluids extraction in wells is an ancient practice that goes from the most traditional, with the construction of shallow wells without any casing pipe and the collection at the bottom and the extraction of fluids to the surface, where the extraction of the well is done using buckets hoisted with a rope, to the most complex and sophisticated systems, such as those used in the oil industry, where the casing pipe of the well is installed with features and special metallurgy, installing it throughout the well, including the producing area, where the hydrocarbons to extract are found. The fluids coming from the producing area enter the well and continue their displacement to the surface coming out of the well by their own energy. These wells are called naturally flowing wells, when the hydrocarbon energy depletes within the producing area as a result of the low gas content in the oil solution. We are in the presence of the so called artificial lift wells, where it is necessary the use of machinery, techniques and systems to draw the remaining fluids at the bottom of the well. Nowadays, the oil industry has an important amount of wells in which hydrocarbon must be sought where it is, in the depth, machines, techniques and systems are expensive consequently it is necessary to install permanently pipes, parts and equipment within the casing pipe of the well, and on the surface to place machinery to move and operate the parts and equipment installed in the casing pipe of the well, and this requires much more energy in its operation, and personnel in the field who are monitoring and repairing this machinery. One of the most commonly used systems is called mechanical pumping. Production pipes are installed in the casing pipe of the well, which come from the producing area to the surface connected section by section in the form of a string, and the mechanical anchor is placed in the lower pipe which is located opposite to the producing area, which is attached to the casing pipe of the well, to prevent the movement of the production pipes. Within the production pipes the down-hole pump with reciprocating mechanism is lowered, and this pump is attached by screwing, at the top, a continuous rod assembly, which reaches the surface as a continuous string. In the last rod on the surface, the tubular parts of final adjustment are screwed to connect to the walking beam machine which is located on the right side of the well on the surface. The walking beam machine supplies all the energy to the rod string and to the down-hole pump with a reciprocating mechanism. This walking beam machine has uninterruptedly reciprocating cyclical movements downward and upward and, with these movements, the down-hole pump with reciprocating mechanism moves and activates, i.e., when it descends draws the fluid from the producing area introducing it into the production pipes, and when it ascends compresses the fluid that is within the production pipes, pushing the oil out of the well on the surface.
The mechanical pumping system has problems such as the frictional wear of its parts, the rods are in constant contact with the production pipes and the interrupted movement between these two components ends up breaking by fatigue. All production pipes, parts and equipment that are installed permanently within the casing pipe of the well generate an investment for clients since they have to buy these materials, i.e., the walking beam machine is rented per daily rate, qualified personnel are required to technically inspect three times a week the whole mechanical pumping system in order to ensure its proper operation and, if necessary, make the required repairs. This is a system used by the industry but with a high investment cost per well: 120 thousand US dollars for the purchase of parts and equipment installed in the well, and 7 thousand US dollars, the cost of monthly rent, for the walking beam machine.